I've only played a couple of hours to X2 because I don't want to spoil my self. While it seems promising, I cannot avoid to complain a bit about 'TUs'. TUs are the "action points" on this game of each soldier in each turn.
I feel they are too limiting at the moment of move a soldier. I know you try to mimic the original UFO: Enemy unknown (which I played countless hours!), but I think the times have changed a bit. Being able to move and shot with at least a 40% of chances to hit, would give another feeling to the game. Now you only can move 4-5 cells and then do a quick shot. The most of turns you have to think if moving or firing, or leave some TUs for reaction. This also do the game very (VERY) slow, and missions can become repetitive pretty soon.
In my opinion, the good thing about XCOM: Enemy unknown / Enemy within, is you can move enough distance, and you can shot with great accuracy. This does the missions very fun, and they are far from being tedious! I replayed that game several times and I don't find it boring, I do again and again the field missions because I feel they're pretty dynamic, and the music is pretty good too!. While with Xenonauts 1, I only played it twice, because it gave me that 'lazy' feeling about the missions (fortunately we had airstrike!). That's mainly because Xenonauts 1 move system.
I'm not asking you change your system about TUs, but you could do it a bit more dynamic, doing the movement would be more easy. Take a look to the picture. I just spotted an alien, moving 6 squares to take advantage from a cover eats all my turn! (almost, I would have 12 from 47 TUs, which are pretty limiting and boring). This forces me to do weird things, like firing without cover with my 8 soldiers to try to kill the alien - bad thing because aliens have better aiming and damage!
btw: In early stage of the game, I find rifles have pretty poor performance when you compare them with shotguns, which allow you can move more and have more chances to hit! and harder!